High hypoxia inducible factor-1α expression is associated with reduced survival in patients with breast cancer: A meta-analysis

Table 2 Meta-analysis results and sensitivity analysis

Analysis	Number of studies	Pooled HR ratio (95%CI)	I2 statistic (%)	χ2 P value for heterogeneity	Analytical model	P value for overall effect
Primary analyses
OS	28	1.47 (1.29-1.69)	65	< 0.00001	REM	< 0.00001
DFS	29	1.82 (1.56-2.12)	71	< 0.00001	REM	< 0.00001
Sensitivity analyses
OS
Exclusion of study with the largest effect size[42]	27	1.51 (1.31-1.74)	62	< 0.0001	REM	< 0.00001
Sample size ≥ 200[12,19,26,33,34,37,38,52,53]	9	1.20 (1.06-1.36)	48	0.05	FEM	0.004
NOS scoring ≥ 7[12,13,19,20,32,37,53]	7	1.46 (1.08-1.97)	62	0.02	REM	0.02
DFS
Exclusion of study with the largest effect size[34]	28	1.88 (1.60-2.22)	69	< 0.00001	REM	< 0.00001
Sample size ≥ 200[16,19,21,28,33,34,37,44,51-53]	11	1.44 (1.21-1.71)	63	0.003	REM	< 0.0001
NOS scoring ≥ 7[16,19-21,32,36,37,45,53]	9	1.57 (1.24-1.99)	63	0.005	REM	0.0002

HR: Hazard ratio; CI: Confidence interval; NOS: Newcastle-ottawa scale; OS: Overall survival; DFS: Disease-free survival; FEM: Fixed-effects model; REM: Random-effects model.